Question: What is the subitem of an oxygen cycle that has an oxidation state of -2.0?
Paraphrase: What is the subitem of an oxygen cycle that has an oxidation state of -2.0?
SPARQL (Wikidata): SELECT ?answer WHERE { wd:Q1140866 wdt:P1269 ?answer . ?answer wdt:P1121 ?x FILTER(contains(?x , '-2.0'))}